JPH10301383A - Developer quantity detecting method and developing device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a developer quantity detecting method capable of detecting the remaining amount of developer housed in a developer container accurately at any time, without irregularities in circulation for carrying the developer from the developer container to a developer carrier and the abnormality of the holding distribution of the developer on the developer carrier quickly/surely. SOLUTION: In the developer quantity detecting method attempted in a developing device 6 provided with a freely rotatable developing sleeve 8 and a developing container 7 carrying the developer container, the developing sleeve 8 receives at least one of DC and AC biases, to be vibrated and a vibration detecting sensor 9 provided in the developing device 6 detects the remaining amount of toner housed in the developing container 7, based on the frequency of the vibration which is propagated from the developing sleeve 8 through at least one of the toner and the developing container 7 as a medium.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a developer amount detecting method for detecting the remaining amount of developer contained in a developer container and a developing device using the method. The present invention relates to a developer amount detecting method for detecting the remaining amount based on a vibration propagating using at least one of the developer container and the developer as a medium, and a developing device using the same.

[0002]

2. Description of the Related Art As an example of a conventional image forming apparatus, a laser printer (hereinafter simply referred to as a printer) 100 disclosed in JP-A-08-160834 is known.
FIG. 11 is a main sectional view showing a schematic configuration of the printer 100.

The printer 100 includes a laser optical system 101 that modulates and emits a laser beam L synchronized with an image signal based on reading of a document or the like, a process cartridge 102 that is detachable from the printer 100, A transfer roller 112 for transferring a copy image based on the recording paper P as a sheet-like transfer material, and a fixing device 11 for fixing an unfixed image to the recording paper P by applying heat and applying pressure.
5 is provided.

As shown in FIG. 12, a process cartridge 102 which is detachable from the printer 100 includes a photosensitive drum 103 serving as an image carrier, a charging roller 104 serving as image forming preparation means, a developing device 105, and an image forming preparation device. And a cleaner 109 serving as a means. FIG. 12 is a main sectional view showing a schematic configuration of the process cartridge 102.

That is, the process cartridge 10
No. 2 is intended to simplify and speed up operations such as replacement and repair of various devices by replacing them with a new process cartridge 102 when replacement or repair of various devices responsible for image formation is required. .

The photosensitive drum 103 held by the process cartridge 102 is rotatable and carries an electrostatic latent image and a developer image (developed image) based on the image signal so as to be transported in the direction of arrow R. It has become.

The charging roller 104 held in the process cartridge 102 is applied with a DC bias and an AC bias in a superimposed manner. The charging roller 104 is charged at a preset timing or the like to prepare for the next image formation. The surface is uniformly charged.

Accordingly, the surface (charged area) of the photosensitive drum 104 uniformly charged by the charging roller 104 is irradiated with the laser light L modulated and emitted from the laser optical system 101 to expose the surface. An electrostatic latent image based on the image signal is formed in the charged area.

The developing device 105 held by the process cartridge 102 has a developing container 106 having a toner container 106A capable of storing a predetermined amount of developer (hereinafter, abbreviated as toner) as a developer container. And a developing sleeve 107 as a developer carrier.

A developing sleeve 107 of the developing device 105 is rotatably supported by a developing container 106, and a toner bias is applied by superimposing a DC bias and an AC bias which are biases for development. Housing 1
The toner contained in the photosensitive drum 103 is selectively carried and conveyed in synchronization with the latent image area of the photosensitive drum 103.

Therefore, the developing sleeve 107 selectively carries the toner and transports the toner to the electrostatic latent image.
A visual image based on the image signal is formed on the surface of the photosensitive drum 103.

The toner container 106A of the developing container 106 has a developing sleeve 107 rotatably supported by a shaft, and an antenna 108 serving as a developer amount detecting means for detecting the remaining amount of the stored toner. Accommodation section 10
It is provided to be stretched inside 6A.

That is, the antenna 108 extended to the toner storage section 106A is connected to the toner stored in the toner storage section 106A based on the capacitance between the antenna 108 and the developing sleeve 107 to which a bias for development is applied. It is designed to detect the remaining amount.

Therefore, in the printer 100, when the capacitance value measured by the antenna 108 is a predetermined value, that is, when the remaining amount of toner in the toner storage section 106A is an amount that requires replenishment, When the value reaches the indicated value, the user is notified that toner needs to be supplied to the toner storage unit 106A.

The cleaner 109 held by the process cartridge 102 removes a residue such as a toner and a piece of paper remaining on the surface of the photosensitive drum 103 based on the completion of the transfer by a cleaning blade 110, and removes the obtained residue. The toner is stored in the waste toner storage unit 111 so as to prepare for the next image formation.

A transfer roller 112 provided in the printer 100 is fed from a paper feed cassette 113 or the like that stores recording papers P classified in a predetermined size or the like in advance, and is transferred by a registration roller 114 at a predetermined timing or the like. The non-transfer surface, which is one surface of the conveyed recording paper P, is charged to a polarity opposite to that of the toner.

Therefore, the recording paper P having the non-transfer surface charged by the transfer roller 112 with the polarity opposite to that of the toner.
The transferred image (toner image) carried on the surface of the photosensitive drum 103 is transferred by Coulomb force or the like.

In the fixing device 115 provided in the printer 100, two rotatable rollers 116 and 117 formed in a roll shape are supported by a pressing mechanism (not shown) so as to be capable of being pressed against the roller. At least one of the rollers 116 and 117 is provided internally with a heater (not shown) such as a halogen lamp as a heat supply source.

Therefore, the recording paper P carrying the toner image (unfixed image) based on the image signal is formed by two rollers 116,
An unfixed image is fixed by the heat supply and pressure applied while being held and conveyed at 117, and thereafter, the sheet is discharged onto a tray 119 or the like by a discharge roller 118, thereby performing a series of copying processes. Ends.

Therefore, in the printer 100,
The capacitance value measured by the antenna 108 is a predetermined value,
That is, when the remaining amount of the toner in the toner storage unit 106A reaches the value indicated when the amount of toner needs to be replenished, the user is notified of the necessity of the toner supply to the toner storage unit 106A, and By replacing the process cartridge 102 holding the developing container 106 requiring toner supply with a new process cartridge 102, the user can easily and quickly clean peripheral devices of the developing device 105 without toner. Thus, the toner is supplied to the toner container 106A.

[0021]

However, in the method for detecting the amount of developer performed by the printer 100, the toner container 1 is not bent when the antenna 108 is bent.
06A, the antenna 108
In such a case, an error such as a variation or deviation may occur in the measured capacitance value, and the user may not be able to accurately inform the user of the replacement time of the process cartridge 102 based on the replenishment of the toner into the toner container 106A. there were.

In the developer amount detecting method performed by the printer 100, the antenna 108 is provided inside the toner container 106A, so that the toner is conveyed to the developing sleeve 107. The flow of the toner may be blocked by the antenna 108, and the circulation efficiency for transporting the toner to the developing sleeve 107 may be deteriorated.

On the other hand, the developer amount detecting method which has been conventionally performed is based on the antenna 10 represented by the printer 100 described above.
8, a developer amount detecting method utilizing a piezo effect, an optical sensor through a light-permeable window formed at least at a portion of the outer wall surface of the developer container, There are known a developer amount detecting method for optically detecting the remaining amount of the developer stored in the developer container, and a developer amount detecting method utilizing the Hall effect.

Here, the above-mentioned method of detecting the amount of developer utilizing the piezo effect is to measure a pressure value received from a peripheral developer by a piezoelectric element having a piezo effect disposed inside a developer container. And a method for detecting the remaining amount of the developer contained in the developer container.

The above-described method for detecting the amount of developer utilizing the Hall effect is a method performed when the developer has magnetism, and a Hall element having a Hall effect disposed in the developer container is used. In this method, the remaining amount of the developer contained in the developer container is detected by measuring the magnetic flux density transmitted from a developer carrier having magnetism using a peripheral magnetic developer as a medium.

However, in the above-described developer amount detecting method utilizing the piezo effect, the developer amount detecting method utilizing the optical sensor, and the developer amount detecting method utilizing the Hall effect, Even in the mass detection method, it is not possible to detect all of the developer contained in the developer container as a detection target.

That is, in the above-described method for detecting the amount of developer utilizing the piezo effect, the piezoelectric element measures the pressure value received from the peripheral developer to determine the remaining amount of developer contained in the developer container. Since the detection is performed, only a limited developer that is in the vicinity of the arrangement position of the piezoelectric element cannot be a target that can be detected.

In the above-described method for detecting the amount of developer using an optical sensor, the remaining amount of the developer contained in the developer container is detected through a window formed in the developer container. Therefore, only a limited developer that is located at a site that can be detected through a window in the inside of the developer container can be a target that can be detected.

Further, in the above-described method for detecting the amount of developer utilizing the Hall effect, the Hall element includes a developing element which is based on a magnetic field transmitted from a developer carrier using a peripheral magnetic developer as a medium. Since the remaining amount of the magnetic developer contained in the developer container is detected, only a limited magnetic developer that is located near the position where the Hall element is disposed cannot be a target that can be detected.

Therefore, in the above-described method for detecting the amount of developer using the piezo effect, the method for detecting the amount of developer using the optical sensor, and the method for detecting the amount of developer using the Hall effect,
When the distribution of the developer contained in the developer container is uneven, or when the amount of the developer is small only in the detectable region in these methods, the developer contained in the developer container is The remaining amount cannot be accurately detected.

Therefore, in the above-described method for detecting the amount of the developer using the piezo effect, the method for detecting the amount of the developer using the optical sensor, and the method for detecting the amount of the developer using the Hall effect, a sufficient amount of development is required. In some cases, an excessive amount of developer is supplied to a developer container containing the developer.

Further, when the developer contained in the developer container is in a state of poor stirring, the above-mentioned distribution of the developer carried on the developer carrier is not uniform, but the above-mentioned distribution is not achieved. In the developer amount detecting method utilizing the piezo effect, the developer amount detecting method utilizing the optical sensor, and the developer amount detecting method utilizing the Hall effect, the abnormal distribution of the developer carried on the developer carrying member is determined. It cannot be detected.

Therefore, in the above-described image forming apparatus utilizing the developer amount detecting method utilizing the piezo effect, the developer amount detecting method utilizing the optical sensor, and the developer amount detecting method utilizing the Hall effect, It was also impossible to prevent abnormalities such as variations in the supply amount of the developer to the image carrier caused by the developer carrier having an uneven distribution of the carrying amount.

Accordingly, the present invention provides a method for accurately determining the remaining amount of the developer contained in the developer container at any time without disturbing the circulation for transporting the developer from the developer container to the developer carrier. It is an object of the present invention to provide a developer amount detecting method and a developing device using the same, which can detect the abnormality of the distribution of the developer carried on the developer carrier quickly and reliably. .

[0035]

According to the present invention, the object is to provide a developer container for storing a developer, a developer carrier, and a residual amount of the developer stored in the developer container. A developer amount detecting method for detecting the remaining amount of the developer in the developer container performed by the developing device having the developer amount detecting means for detecting the amount of developer. Is vibrated using at least one of the developer and the developer container as a medium, and the vibration propagated by the developer amount detecting means using at least one of the developer and the developer container as a medium. Is achieved by detecting the frequency or amplitude of the developer and measuring the remaining amount of the developer in the developer container based on the detected value.

The object of the present invention is that in the first aspect, the developer amount detecting means detects a frequency of vibration transmitted by using at least one of the developer and the developer container as a medium, and Is also achieved by the second invention that vibrates so that the frequency can be changed.

Further, the object of the present invention is that in the first aspect, the developer amount detecting means detects the amplitude of the vibration propagated using at least one of the developer and the developer container as a medium, and Is also achieved by the third invention in which the vibration is changed.

The above object is also achieved by a fourth invention in any one of the first to third inventions, wherein the developer carrier vibrates also as a vibrating means. You.

Further, the above object is achieved according to any one of the first to third aspects of the present invention, wherein the image carrier provided in the image forming apparatus which can utilize the developing device also serves as the vibration means. This is also achieved by the fifth invention that vibrates.

The object of the present invention is to provide a method according to any one of the first to third inventions, wherein the image carrier is uniformly charged in order to prepare for the next image formation. The present invention is also attained by the sixth invention in which the image forming preparation means provided in the image forming apparatus for removing the body residue vibrates also as the vibration means.

Further, the object is to provide a developer accommodating member for accommodating a developer, a developer carrying member, and a developer amount detecting means for detecting a remaining amount of the developer accommodated in the developer accommodating member. A developing device having at least one of the developer and the developer container as a medium, a vibrating unit configured to vibrate so that a frequency or an amplitude can be changed, and the developer amount detecting unit includes the developer or the developer. This is also achieved by the seventh invention in which the frequency or amplitude of the vibration propagated using at least one of the containers as a medium is detected, and the remaining amount of the developer in the developer container is measured based on the detected value. Is done.

That is, in the first aspect of the present invention, the vibration from the vibrating means propagates through the developer container and the developer stored in the developer container to the developer amount detecting means.

According to the second aspect of the invention, the frequency-changed vibration output from the vibrating means propagates through the developer container and the developer contained therein to the developer amount detecting means. While propagating, vibrations having different frequencies are generated from the vibration means.

Further, in the third aspect of the invention, the vibration of which amplitude is output from the vibrating means propagates through the developer accommodating body and the developer accommodated therein to the developer amount detecting means. While propagating, vibrations having different amplitudes are generated from the vibration means.

In the fourth aspect of the present invention, the vibration from the developer carrier, which also serves as the vibration means, propagates through the developer container and the developer contained therein to the developer amount detecting means. As the light propagates, the developer carrying member also functions as a vibration unit.

Further, in the fifth aspect of the invention, the vibration from the image carrier which also serves as the vibration means propagates through the developer container and the developer contained therein, and propagates to the developer amount detecting means. In addition, the image carrier also functions as a vibration unit.

In the sixth aspect of the invention, the vibration from the image forming preparation means also serving as the vibration means propagates through the developer container and the developer contained therein to the developer amount detecting means. As the light propagates, the image forming preparation means also serves as the vibration means.

Further, in the seventh invention, the vibrating means vibrates so as to be able to change the frequency or amplitude by using at least one of the developer and the developer container as a medium, and the developer amount detecting means comprises the developer amount detecting means. Alternatively, the remaining amount of the developer in the developer container is measured based on a value detected by detecting a frequency or an amplitude of the vibration transmitted using at least one of the developer containers as a medium.

[0049]

Embodiments of the present invention will be described with reference to the accompanying drawings.

(First Embodiment) First, a developer amount detecting method according to a first embodiment of the present invention and an image forming apparatus 1 as an example of an image forming apparatus suitable for utilizing this method will be described with reference to FIGS. A description will be given based on any one of FIGS. FIG. 1 is a main cross-sectional view illustrating a schematic configuration of the image forming apparatus 1.

The image forming apparatus 1 is connected to an external device (not shown) such as a computer or a word processor as a host for providing image information serving as a document.
This is an image forming apparatus in which the setting of the density of a copied image, the number of sheets of recording paper P to be copied, and the like, and a command to start copying are made from the external device.

The image forming apparatus 1 includes a laser optical system 2 that modulates and emits a laser beam L based on image information provided from an external device, an image forming unit 3 that forms an image based on the above-described image information, A fixing device 16 for fixing an unfixed image to the recording paper P by applying heat and applying pressure.

As shown in FIG. 2, the image forming section 3 provided in the image forming apparatus 1 includes a charging roller 4 as image forming preparation means, a photosensitive drum 5 as an image carrier, and a developing device 6 described below. , A transfer roller 11 and a cleaner 13 as image forming preparation means. FIG. 2 is a main cross-sectional view showing a schematic configuration of the image forming unit 3.

The charging roller 4 of the image forming section 3
Is a device for uniformly charging the surface of the photosensitive drum 5 in preparation for the next image formation, and improves a DC bias for setting a charge value and uniformity and convergence of the charge value. AC bias is applied in a superimposed manner.

The photosensitive drum 5 of the image forming unit 3
In the present embodiment, is formed of a material such as OPC or amorphous silicon, is rotatably supported by the image forming apparatus 1, and performs laser optics on a charged area charged by the charging roller 4. The exposure of the laser light L modulated and emitted from the system 2 forms an electrostatic latent image based on the image information described above.

Transfer Roller 11 of Image Forming Unit 3
Is a paper feed cassette 12 provided in the image forming apparatus 1.
After the non-transfer surface, which is one surface of the recording paper P fed and conveyed at a predetermined timing or the like, is charged to a polarity opposite to that of the developer (hereinafter, simply referred to as toner), The visible image (toner image) carried on the photosensitive drum 5 is transferred to the transfer surface, which is the other surface of the recording paper P.

The cleaner 13 provided in the image forming apparatus 1 removes toner and paper chips remaining on the surface of the photosensitive drum 5 due to the end of the previous image formation, thereby preparing for the next image formation. And has a cleaning blade 14 and a waste toner storage unit 15.

That is, the cleaner 13 scrapes off the residue on the surface of the photosensitive drum 5 with the cleaning blade 14 and stores it in the discharged toner storage unit 15 to prepare for the next image formation. .

As shown in FIG. 1, the fixing device 16 provided in the image forming apparatus 1 can contact one of the toner image carrying surface and the non-toner image carrying surface of the recording paper P. The rollers 17, 18 are pivotally supported together.

The above-mentioned fixing device 16 is provided with two rollers 17,
18 are pressurized by a pressurizing mechanism (not shown) provided in the fixing device 16 so as to press against each other via the recording paper P.

At least one of the rollers 17 and 18 has a heating means serving as a heat supply source for the recording paper P carrying the unfixed image, for example, a heater (not shown) such as a halogen lamp. But. It is provided internally.

That is, in the fixing device 16,
The recording paper P on which the transfer of the toner image (unfixed image) based on the image information by the transfer roller 11 is not fixed by applying heat and applying pressure while being nipped and transported between the rollers 17 and 18. The image is fixed by melting and mixing.

In the image forming apparatus 1 having the above configuration,
A series of copying processes is performed in the following manner.

First, based on image information provided from an external device as a host, the laser light L
Is modulated to emit light.

On the other hand, the photosensitive drum 5 is uniformly charged at a predetermined timing or the like by the charging roller 4 to which a DC bias and an AC bias are superimposed and applied in accordance with a copy start command from an external device. You.

Accordingly, the laser L modulated and emitted from the laser optical system 2 irradiates the charged area of the photosensitive drum 5 and exposes the charged area, so that an electrostatic latent image based on the image information is formed on the surface of the photosensitive drum 5. Formed and carried.

On the other hand, the recording paper P on which an image is formed based on the above-described image information is fed from the paper feed cassette 12 or the like a predetermined time after the start of copying, and the top sensor 19 installed in the image forming apparatus 1 is used. Conveyed toward.

Next, at the same time or almost at the same time that the leading end of the recording paper P fed and conveyed from the cassette 18 arrives at the top sensor 19, the developing device 6 transfers the recording paper P to the latent image carrying area of the photosensitive drum 5. The application of the toner is started.

Therefore, a toner image is formed on the surface of the photosensitive drum 5 based on the image information.

Next, the top sensor 19 operates at a predetermined timing or the like so that the toner image carried on the surface of the photosensitive drum 5 is transferred to a position along the above-mentioned image information on the transfer surface of the recording paper P. It is conveyed toward the transfer roller 11.

The recording paper P conveyed from the top sensor 19 at a predetermined timing or the like is charged by the transfer roller 11 on the non-transfer surface to a polarity opposite to that of the toner, and is carried on the surface of the photosensitive drum 5. The transferred toner image is transferred to a transfer surface, and then conveyed to the fixing device 16.

Accordingly, the surface of the photosensitive drum 5 on which the toner image has been transferred onto the recording paper P is subjected to removal of the residue by the cleaner 12 and uniform charging by the charging roller 4 to form the next image. Be prepared for formation.

On the other hand, the recording paper P on which the toner image has been transferred by the transfer roller 11 is
The unfixed image is fixed by the heat supply and pressure applied while being conveyed while being held between the sheets 7 and 18, and is further discharged to a tray 21 or the like by a discharge roller 20 installed in the image forming apparatus 1. Thus, a series of copying processes in the image forming apparatus 1 is completed.

In the present embodiment, as shown in FIGS. 3 and 4, the developing device 6 included in the image forming unit 3 has a developing device having a toner container (not shown) as a developer container. Container 7 and developing sleeve 8 as a developer carrier
And a vibration detecting sensor 9 as a developer amount detecting means. FIGS. 3 and 4 are a main sectional view and a perspective view, respectively, of the developing device 6.

As shown in FIG. 4, the developing container 7 of the developing device 6 is formed so as to be mirror-symmetrical or almost mirror-symmetrical with respect to the plane of mirror symmetry in the axial direction of the developing sleeve 8, and a predetermined amount of toner is The developing container 7 can be accommodated.
Inside, a stirring member 10 for mechanically dissolving the toner so as to smoothly carry the stored toner to the developing sleeve 8 is rotatably supported.

The developing sleeve 8 of the developing device 6
Is rotatably supported by the developing container 7, and a doctor blade (not shown) provided in the developing device 6 optimizes the amount of toner carried.

In the present embodiment, the developing sleeve 8 is made of a member formed by forming a blasted aluminum into a roll having an outer diameter of 12 mm and a thickness of 0.8 mm in a diameter direction. A flange having an axial length of 14.5 mm and a diameter of 6 mm is inserted into the hollow portion of the developing sleeve 8.

In the present embodiment, blasted aluminum is used as the material of the developing sleeve 8 as the developer carrying member. However, the material is not limited to this material. Examples thereof include aluminum that has been coated, non-magnetic stainless steel that has been blasted or coated, and the like.

In a developing device using a developer having magnetic properties (magnetic toner), a cylindrical magnetic material, for example, a magnet roller is coaxially mounted on a hollow portion of a developing sleeve 8 as a developer carrier. What is necessary is just a fixed form.

The developing sleeve 8 having the above configuration includes
In the present embodiment, a DC bias of 630 V is used as a bias for development so that the application of toner to the electrostatic latent image carried on the surface of the photosensitive drum 5 can be selected.
An AC bias of a rectangular wave having a peak width Vpp of 1200 V and a frequency of 1800 Hz (see FIG. 5A) is applied in a superimposed manner.

Therefore, the developing sleeve 8 and the photosensitive drum 5
And the vibration electric field based on the AC bias described above is generated, and the vibration sleeve causes the developing sleeve 8 to vibrate in the developing container 7. Therefore, in the present embodiment, the developing sleeve 8 is Of the vibration means.

Therefore, the vibration of the developing sleeve 8 generated by the oscillating electric field propagates to the vibration detecting sensor 9 using the developing container 7 and the toner contained therein as a medium.

The vibration detecting sensor 9 of the developing device 6
In the present embodiment, for example, a piezoelectric element or the like utilizing the piezo effect is used, and the vibration propagated as a medium using at least one of the developing container 7 and the toner contained in the developing container 7 (see FIG. ) Is measured to measure the remaining amount of toner stored in the toner storage unit (hereinafter, this amount is referred to as a remaining toner amount).

Therefore, the vibration detecting sensor 9 detects the vibration of the developing container 7 or at least one of the toners contained in the developing container 7 in order to satisfactorily detect the vibration.
Is mounted at or near the intersection of the outer wall surface and the mirror symmetry plane.

In the present embodiment, the vibration sensor 10 is vibrated by applying the AC bias shown in FIG.
The input waveform shown in (b) is obtained.

In the developing device 6, it is considered that the main medium of the vibration of the developing sleeve 8 changes due to a change in the remaining amount of the toner stored in the toner storing section. .

That is, when a sufficient amount of toner is stored in the above-described toner storage section, it is considered that the medium for transmitting the vibration of the developing sleeve 8 is mainly toner, while the remaining amount of toner is It is considered that the medium for propagating the above-mentioned vibration is mainly the outer wall surface of the developing container 7 as the number decreases.

Therefore, in the present embodiment, in order to confirm the responsiveness of the vibration sensor 9 to the change in the remaining amount of the toner stored in the toner storing section, when the toner remaining amount is sufficient or almost empty. FIG. 6 shows response waveforms of the vibration detection sensor 9 corresponding to each case. FIGS. 6A and 6B show response waveforms corresponding to the case where the toner amount is sufficient or almost empty, respectively.

As can be understood from a comparison between FIG. 6A and FIG. 6B, the vibration detecting sensor 9 shown in FIG.
According to the rise and fall of the AC bias of
Since the fall and rise of the response waveform are detected, and the amplitude of each response waveform changes according to the change in the remaining amount of the toner stored in the toner storage unit described above,
In the developer amount detection method according to the present embodiment, an advantage that good responsiveness to a change in the remaining amount of toner is obtained is obtained.

By setting the mounting position of the vibration detecting sensor 9 as in this embodiment, the developing container 7
Or, since vibration transmitted through at least one of the toners contained in the medium as a medium is uniformly detected with respect to the mirror symmetry plane, an isotropic or almost isotropic detection result without bias is obtained. There is also obtained an advantage that the remaining amount of the toner stored in the toner storing section can be accurately detected.

Further, in the present embodiment, since the vibration generated from the developing sleeve 8 propagates through the developing container 7 and the toner contained in the developing container 7 completely, any abnormality in the developing device 6, for example, When the toner carrying distribution of the developing sleeve 8 is abnormal or the like, an advantage can be obtained that the response waveform of the vibration detecting sensor 9 easily appears.

Therefore, in the developing device 6, the peak width Vpp (double the amplitude value) of the response waveform of the vibration detection sensor 9 is 0.5 mV, based on the measurement results and the like made in advance.
When the values indicate 0.4 mV and 0.32 mV, the external device as a host which has received the electric signal corresponding to each measurement value from the vibration detection sensor 9 outputs the remaining amount of toner stored in the toner storage unit. 100%, 50% and 1
0% is transmitted to the user. In particular, when Vpp of the response waveform of the vibration detection sensor 9 indicates 0.31 mV or less, a warning indicating the necessity of toner supply from the external device to the user is issued. I made it.

In this embodiment, only when the remaining amount of the toner stored in the toner storing portion built in the developing container 7 indicates the predetermined value as described above, the toner remaining amount from the external device is determined. A value or a warning indicating the necessity of replenishing the toner is displayed. However, the above-mentioned external value may be displayed in accordance with each of the remaining amount of toner from 100% to 0% based on a measurement result made in advance. The device can also notify the user at any time.

Therefore, in the developing device 6 having the above-described structure, the vibration from the developing sleeve 8 also serving as the vibration means propagates through the developing container 7 and the toner contained in the developing container 7 to the vibration detecting sensor 9. Therefore, information about the remaining amount of toner contained in the toner containing portion of the developing container 7 and the distribution of the toner carried on the developing sleeve 8 can be transmitted to the vibration detection sensor 9. Therefore, the user can always know the remaining amount of the toner in the developing container 7 at the present time, and also can surely and quickly know the abnormality of the distribution of the toner carried on the developing sleeve 8. Since stable high-quality image formation can be performed for a long period of time, and the developing sleeve 8 also serves as a vibrating means, the configuration of the developing device 6 is unnecessarily increased. It can also be suppressed to compact without.

In the present embodiment, the rectangular wave shown in the figure is used as the AC bias for vibrating the developing sleeve 8, but the present invention is not limited to this.
A sine wave shown in FIG. 7A, a triangular wave (not shown), or the like may be used. When the sine wave shown in FIG. 7A is used as an AC bias for vibration, the vibration detection sensor 9 is used. 7B, a response waveform as shown in FIG. 7B is obtained according to a change in the remaining amount of the toner stored in the toner storage portion of the developing container 7.

Further, in the present embodiment, the vibration detecting sensor 9 mounted in contact with the outer wall surface of the developing container 7 is used as the developer remaining amount detecting means. However, the present invention is not limited to this. If a sensor capable of detecting an acoustic signal represented by a sound wave or the like, for example, a microphone is used as the developer remaining amount detecting means, the developing sleeve 8
It is not necessary to directly attach the developing container 7 to the developing container 7 as long as the position is at a position where the vibration generated from the above can be detected.

(Second Embodiment) Next, a developer amount detecting method according to a second embodiment of the present invention will be described with reference to FIGS. FIG. 8 is a graph showing sensitivity characteristics with respect to frequency of a representative sensor used for the developer amount detecting means. FIG. 9 is a perspective view and a main cross-sectional view showing a schematic configuration of the developing device. The image forming apparatus and the developing apparatus that can utilize the developer amount detecting method of the present embodiment have the same configuration as the image forming apparatus 1 and the developing apparatus 6 described in the first embodiment. Description will be omitted in place of 1, FIG. 3 and FIG.

In the first embodiment, the purpose of the present invention is achieved by applying a bias for vibration to the AC bias developing sleeve 8 having a constant frequency.

That is, in the first embodiment, the AC bias of FIG. 5A applied to the developing sleeve 8 serves as both a bias for development and a bias for vibration. The developer amount detecting means capable of detecting the AC bias is selected and attached to the developing container 7, thereby achieving the purpose of the present invention.

However, in order to expand the versatility of the developer detecting means that can be used in the present invention, it is more desirable that the bias applied to the developing sleeve 8 for vibration can be changed in frequency.

The reason for this is that sensors and the like that can be used as the developer amount detecting means of the present invention include, as shown in FIG.
Frequently used bias frequency for development, for example much higher than 2000 Hz, for example 60
This is because many sensors have a sensitivity peak with respect to an AC bias of 00 Hz.

FIG. 8 shows the characteristics (solid line) of the sensor within the frequency range of the AC bias normally used as the bias for development, and the characteristics (dashed line) of the sensor having no sensitivity peak width Vpp in this frequency range. ).

Therefore, in the present invention, as shown in FIG. 9A, when the remaining amount of toner contained in the toner container (not shown) of the developing container 7 is detected, the developing sleeve 8 is used. A rectangular wave AC bias having a frequency of 6000 Hz is applied as a bias for vibration. On the other hand, when a developing operation is performed in the developing device, the developing sleeve 8 has a frequency of 2000 as a bias for developing.
9B, so that an AC bias of a rectangular wave of 1 Hz is applied, whereby the S / N ratio of the vibration detection sensor 9 is lower than that of the response waveform in the first embodiment, as shown in FIG. A large response waveform with high response was obtained.

Therefore, not only the same effects and advantages as those of the first embodiment can be obtained, but also an AC bias having a different frequency is applied to the developing sleeve 8 as a bias for vibration. And the versatility to the types of sensors that can be used as the developer amount detecting means.

As in the present embodiment, the timing of applying a bias higher than the AC bias in the normally used frequency range to the developing sleeve 8 is set, for example, so that the photosensitive drum can be copied. For example, during the multiple rotations in one direction, or during the period from the end of transfer to an arbitrary recording sheet P to the time when the next recording sheet P reaches the transfer roller 11, the developing sleeve 8 It is possible to prevent disturbance of the distribution of the toner carried on the sheet.

(Third Embodiment) Next, a developer amount detecting method according to a third embodiment of the present invention will be described with reference to FIG. FIG. Note that the image forming apparatus and the developing device utilizing this embodiment have the same configuration and the like as the image forming apparatus 1 and the developing device 6 of the first embodiment. The description is omitted.

In the first embodiment, the purpose of the present invention is achieved by applying a bias for oscillating to the AC bias developing sleeve 8 having a constant amplitude.

That is, in the first embodiment, the AC bias applied to the developing sleeve 8 in FIG. 5A serves as both a bias for development and a bias for vibration. The developer amount detecting means capable of detecting the AC bias is selected and attached to the developing container 7, thereby achieving the purpose of the present invention.

However, in order to expand the versatility of the developer amount detecting means that can be used in the present invention, it is more desirable that the frequency of the bias applied to the developing sleeve 8 for the vibration can be changed. .

The reason is that a sensor or the like that can be used as the developer amount detecting means of the present invention has a peak width Vpp of a bias for development generally used, for example, 1200.
Vpp much higher than V, eg 1800V AC
This is because many sensors have a peak in sensitivity to bias.

Therefore, in the present invention, FIG.
As shown in FIG. 5, when the remaining amount of toner contained in the toner container (not shown) of the developing container 7 is detected, V is applied to the developing sleeve 8 as a bias for vibration.
When a rectangular wave AC bias having a pp of 1800 V is applied, on the other hand, when a developing operation is performed in the developing device, the developing sleeve 8 has a Vpp of 120 as a bias for development.
An AC bias of 0 V rectangular wave is set to be applied, whereby the vibration detection sensor 9 has a lower S / N ratio than the response waveform in the first embodiment, as shown in FIG. A large response waveform with high response was obtained.

Accordingly, not only the same effects and advantages as those of the first embodiment can be obtained, but also an AC bias having a different amplitude is applied to the developing sleeve 8 as a bias for vibration. And the versatility to the types of sensors that can be used as the developer amount detecting means.

As in this embodiment, by applying an AC bias of Vpp higher than the Vpp range of a normally used AC bias to the developing sleeve 8, abnormalities such as fog on the surface of the photosensitive drum 5 are prevented. When there is a risk of occurrence, the photosensitive drum 5 may be used to prevent this.
The sequence control and the like may be set in advance so as to adjust the potential distribution on the surface.

As described above, in the first to third embodiments, as the bias applied to the developing sleeve 8 for vibration, an AC bias that changes depending on time is used. Although the developing sleeve 8 has been used, it is also possible to vibrate the developing sleeve 8 in the developing container 7 by repeatedly switching between applying and blocking an arbitrary DC bias to the developing sleeve 8 as a bias for vibration.

In the first to third embodiments, only the embodiment in which the developing sleeve 8 also functions as a vibrating means has been described. However, the photosensitive drum 5 serving as an image carrier and the charging means serving as an image forming preparation means are provided. Roller 4 and cleaner 1
The effect described above can be similarly obtained by the fact that 3 also serves as the vibration means.

[0116]

As described above, according to the first aspect of the present invention, the vibration from the vibrating means propagates through the developer container and the developer contained therein to detect the amount of the developer. Therefore, information on the remaining amount of the developer in the developer container and the distribution of the developer carried on the developer carrier can be transmitted to the developer remaining amount detecting means. Since the developer can always know the remaining amount of the developer in the developer container at the present time, and can surely and quickly know the abnormality of the developer distribution of the developer carrier, the user Can perform stable high-quality image formation over a long period of time.

In the second aspect of the present invention, the frequency-changed vibration output from the vibrating means propagates through the developer container and the developer contained therein to the developer amount detecting means. Since it propagates, it becomes possible to transmit information on the remaining amount of the developer in the developer container and the distribution of the developer carried on the developer carrying body to the developer remaining amount detecting means.
The user can always know the remaining amount of the developer in the developer container at the present time, and can surely and quickly know the abnormality of the distribution of the developer carried on the developer carrier. The developer can perform stable and high-quality image formation for a long period of time, and furthermore, vibrations having different frequencies are generated from the vibrating means. The versatility can be expanded.

Further, in the third aspect of the invention, the vibration of which amplitude is output from the vibration means propagates through the developer accommodating body and the developer accommodated therein to the developer amount detecting means. Since it propagates, it becomes possible to transmit information on the remaining amount of the developer in the developer container and the distribution of the developer carried on the developer carrying body to the developer remaining amount detecting means.
The user can always know the remaining amount of the developer in the developer container at the present time, and can surely and quickly know the abnormality of the distribution of the developer carried on the developer carrier. The developer can perform stable high-quality image formation for a long period of time, and furthermore, vibrations having different amplitudes are generated from the vibration means. The versatility can be expanded.

In the fourth aspect of the present invention, the vibration from the developer carrier, which also serves as the vibration means, propagates all the way through the developer container and the developer contained therein to the developer amount detecting means. As a result, the information on the remaining amount of the developer in the developer container and the distribution of the developer in the developer carrier can be transmitted to the developer remaining amount detecting means. The user can always know the remaining amount of the developer in the developer container at the present time, and can surely and quickly know the abnormality of the distribution of the developer in the developer carrier, so that the user can stably operate. Since high-quality image formation can be performed for a long period of time, and since the developer carrying member also serves as a vibrating means, the developing device that can utilize these can be suppressed to a compact configuration.

Further, in the fifth aspect, the vibration from the image carrier also serving as the vibrating means propagates through the developer accommodating body and the developer accommodated therein to the developer amount detecting means. Therefore, information on the remaining amount of the developer in the developer container and the distribution of the developer in the developer carrying member can be transmitted to the developer remaining amount detecting means. The user can always know the remaining amount of the developer in the developer container at the present time, and can reliably and quickly know the abnormality of the distribution of the developer in the developer carrier. High-quality image formation can be performed over a long period of time. Further, since the image carrier also serves as a vibrating means, an image forming apparatus that can utilize these can be suppressed to a compact configuration.

In the sixth aspect of the invention, the vibration from the image forming preparation means also serving as the vibration means propagates through the developer container and the developer contained therein to the developer amount detecting means. As a result, the information on the remaining amount of the developer in the developer container and the distribution of the developer in the developer carrier can be transmitted to the developer remaining amount detecting means. The user can always know the remaining amount of the developer in the developer container at the present time, and can surely and quickly know the abnormality of the distribution of the developer carried on the developer carrier. High-quality image formation can be performed for a long period of time, and the image forming preparation means also serves as a vibration means, so that an image forming apparatus utilizing these can be suppressed to a compact configuration.

Further, in the seventh aspect of the invention, the developing device includes a vibrating means for vibrating the frequency or the amplitude so that the frequency or the amplitude can be changed by using at least one of the developer and the developer container as a medium. Since the detecting unit detects the remaining amount of the developer in the developer container based on the frequency or amplitude of the vibration that has propagated using at least one of the developer and the developer container as a medium, The object can be easily solved, and the user can perform stable high-quality image formation for a long period of time.

[Brief description of the drawings]

FIG. 1 is a main cross-sectional view illustrating a schematic configuration of an image forming apparatus according to a first embodiment of the present invention.

FIG. 2 is a main cross-sectional view illustrating a schematic configuration of an image forming unit included in the image forming apparatus of FIG.

FIG. 3 is a main cross-sectional view illustrating a schematic configuration of a developing device included in the image forming unit of FIG. 2;

FIG. 4 is a perspective view illustrating a schematic configuration of a developing device constituting the image forming unit of FIG. 2;

5A and 5B are examples of an input waveform and a response waveform used in a developer amount detection method performed by the developing device of FIG. 3 or FIG. 4; FIG. 5B shows an input waveform, and FIG. 5B shows a response waveform obtained by a vibration detection sensor of the developing device.

6A and 6B are response waveforms corresponding to a specific amount of developer among the response waveforms shown in FIG. 5, wherein FIG. 6A shows a response waveform obtained by a developing device containing a sufficient amount of toner, and FIG. () Shows a response waveform obtained by the developing device in an almost empty state.

FIGS. 7A and 7B show another example of an input waveform and a response waveform used in the developer amount detection method according to the first embodiment of the present invention. FIG. FIG. 3B shows a waveform input to the sleeve, and FIG. 3B shows a response waveform obtained by a vibration detection sensor of the developing device.

FIG. 8 is a graph showing sensitivity characteristics with respect to frequency of a typical sensor used for the developer amount detecting means of the present invention.

9A and 9B are an input waveform and a response waveform used in the developer amount detection method according to the second embodiment of the present invention, and FIG.
3 shows an input waveform to the developing sleeve of the developing device of FIG. 3 or FIG. 4, and (b) shows a response waveform obtained by the vibration detection sensor of the developing device.

FIG. 10 shows an input waveform and a response waveform used in the developer amount detection method according to the third embodiment of the present invention;
(A) shows an input waveform to the developing sleeve of the developing device of FIG. 3 or FIG. 4, and (b) shows a response waveform obtained by a vibration detection sensor of the developing device.

FIG. 11 is a main cross-sectional view illustrating a schematic configuration of an image forming apparatus that can utilize a conventional developer amount detection method.

12 is a main cross-sectional view illustrating a schematic configuration of a process cartridge detachably supported by the image forming apparatus of FIG.

[Explanation of symbols]

 Reference Signs List 4 charging roller (image formation preparing means) 5 photosensitive drum (image carrier) 6 developing device 7 developing container (developer container) 8 developing sleeve (developer carrier) 9 vibration detecting sensor (developer amount detecting means) 13 Cleaner (image forming preparation means)

Claims (7)

[Claims] 1. A developing device comprising: a developer accommodating body for accommodating a developer; a developer carrier; and a developer amount detecting means for detecting a remaining amount of the developer accommodated in the developer accommodating body. In the developer amount detecting method for detecting the remaining amount of the developer in the developer container, the vibrating means provided in the developing device is provided with at least one of the developer and the developer container. A method for detecting the amount of developer, comprising: vibrating one side as a medium; and measuring the vibration transmitted by using at least one of the developer or the developer container as a medium by the developer amount detecting means. 2. A developer amount detecting means for detecting a frequency of a vibration propagated using at least one of a developer and a developer container as a medium, wherein the vibrating means vibrates so that the frequency can be changed. The method for detecting the amount of developer according to claim 1. 3. The developer amount detecting means detects the amplitude of the vibration propagated using at least one of the developer and the developer container as a medium, and the vibrating means vibrates so that the amplitude can be changed. The method for detecting the amount of developer according to claim 1. 4. The developer amount detecting method according to claim 1, wherein the developer carrier vibrates also as vibrating means. 5. The developer according to claim 1, wherein the image carrier provided in the image forming apparatus which can utilize the developing device vibrates also as a vibrating means. Amount detection method. 6. An image forming preparation means provided in an image forming apparatus for uniformly charging an image carrier or removing a residue of the image carrier in preparation for the next image formation also serves as a vibration means. 4. The method according to claim 1, wherein the vibration is caused by
The method for detecting a developer amount according to any one of the above. 7. A developing device comprising: a developer accommodating body for accommodating a developer; a developer carrier; and a developer amount detecting means for detecting a remaining amount of the developer accommodated in the developer accommodating body. A vibration unit that vibrates so as to be able to change the frequency or amplitude using at least one of the developer and the developer container as a medium, and wherein the developer amount detection unit includes the developer or the developer container. A developing device which detects a frequency or an amplitude of the vibration propagated using at least one of the above as a medium and measures the remaining amount of the developer in the developer container based on the detected value.